Cut bacon into ½-inch (1 cm) strips. Cook bacon, over medium heat, in a large heavy skillet until crisp. Remove pork with a slotted spoon and drain on paper towels. Reserve.
Heat 1 tablespoon oil in the same skillet, add the pork and cook over high heat, turning, just until no longer pink. Transfer to a plate.
Add the remaining 1 tablespoon olive oil, onions, and garlic to the skillet and cook, stirring occasionally, until the onions start to turn golden brown. Stir in the chicken broth, wine, if using, vinegar, bay leaves, rosemary, and a pinch of cloves. Cover and bring to a boil. Add the pork and any juices that have accumulated on the plate. Reduce the heat to medium-low, cover, and cook until the pork is just tender.
Remove the bay leaves before serving and stir in the reserved bacon. Season with salt and pepper.